You know you're asking the internet to provide a response that would probably differ from what they would actually do if such a situation occurs... I bet at least a couple of people will say that they will handle the person directly when in reality, they would probably call the cops or avoid it all together or worse, blog about it and think they accomplished something.

Me? The answer isn't hard; Call the cops (that is if I even have my phone on me). Why bother risking my life when I know that the situation could be resolved with the robber arrested and me not bleeding all over in a pool of blood.

Plus, Refer to the Car Hit Baby Girl In China story for an example of the bystander effect.

OH MY GOSH.. The Car Hit Baby Girl in China story was so bad.................

This is pretty much how it may look: Step 1) Mumble curses at people not doing anything; Step 2) Curse at myself for thinking someone else would do something; Step 3) 'Hide' in plain sight and get as much info as I call the cops; Step 4) Exaggerate, exaggerate, exaggerate to friends and family.

Take a deep breath , Knock the robbers down !!..... Then Rob the store , no one would do nothing ,who is the winner?..... me

So your telling me to simply steal money in front of a group of people , and know one would do anything
and the more people around the crime scene , the more chances i wouldn't get caught
Interesting...... I might try it

Well, first I would run to a nearby alleyway and when nobody's looking I would change into my super-man costume. Then I would walk up to the robber fellow and take him out for a steak dinner at the olive garden.

I would and have called the cops in the event of someone being robbed and in the event of a shooting in my neighborhood.

On the other hand, my neighbors aren't quite as conscientious as I am - in fact, the neighbor across the street watched while my house was robbed and never called the cops because he said he was afraid of retaliation (since one of the robbers was my neighbor two houses down).
So would I call the police now to help them out...probably not. I can be pretty vindictive.